1398545640 has 96 divisors (see below), whose sum is σ = 4587878880. Its totient is φ = 369449856.

The previous prime is 1398545623. The next prime is 1398545641. The reversal of 1398545640 is 465458931.

1398545640 is a `hidden beast` number, since 1 + 3 + 9 + 85 + 4 + 564 + 0 = 666.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is not an unprimeable number, because it can be changed into a prime (1398545641) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 20367 + ... + 56673.

It is an arithmetic number, because the mean of its divisors is an integer number (47790405).

Almost surely, 2^1398545640 is an apocalyptic number.

1398545640 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1398545640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2293939440).

1398545640 is an abundant number, since it is smaller than the sum of its proper divisors (3189333240).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1398545640 is a wasteful number, since it uses less digits than its factorization.

1398545640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 36431 (or 36424 counting only the distinct ones).

The product of its (nonzero) digits is 518400, while the sum is 45.

The square root of 1398545640 is about 37397.1341147955. The cubic root of 1398545640 is about 1118.3014325199.

The spelling of 1398545640 in words is "one billion, three hundred ninety-eight million, five hundred forty-five thousand, six hundred forty".